13
(A)
(B)
WARNING
Never loosen the bonnet stud nuts (15) before
releasing the spring tension with the adjusting
bolt (21A).
CAUTION
Do not permit any rocking motion of the spindle
or any other parts while lifting the spindle and
internals out of the body. Any rocking motion
could damage the valve seats.
CAUTION
Do not permit any rocking motion of the spindle
or any other parts while lifting the spindle and
internals out of the body. Any rocking motion
could damage the valve seats.
- After making sure all spring tension has
been released, loosen and remove the
bonnet stud nuts.
- Strap the spring (16) into the bonnet (13)
to prevent the spring from falling out from
between the bonnet struts. Using suitable
lifting means, lift the spring and bonnet
assembly carefully straight up and over the
spindle (12). Set the assembly aside.
- Lay the spindle down horizontally.
- Proceed with disassembly of the internals
according to paragraph below 'Disassembly
of internal structure'.
- Should lack of overhead space prevent the
bonnet (13) being lifted over the spindle (12),
the spindle nut (23) may be installed to hold
the spindle in position. Using suitable lifting
means, lift the superstructure carefully
straight up and out of the body.
- Lay the superstructure down so the spindle
is horizontal. Care must be exercised to
prevent the parts from being damaged.
- Remove the spindle nut (23) from the
spindle (12). Remove the spindle, spring (16)
and washers (17 and 18A) carefully from the
bonnet (13).
- Proceed with disassembly of the internals
according to the following paragraphs.
• Disassembly of internal structure
Remove the guide (9) and guide ring (10) from
the body (1A) as an assembly and unscrew
the guide ring from the guide.
Remove the spindle (12) from the disc
insert (5) by lifting the spindle slightly to
engage the threads and unscrewing the
spindle from the disc insert.
Unscrew the nozzle ring (3) from the
nozzle (1B).
CROSBY
®
STYLES HC AND HCA ISOFLEX™ SAFETY VALVES
INSTALLATION, MAINTENANCE AND ADJUSTMENT INSTRUCTIONS
• Disassembly without retaining spring
compression
To disassemble the safety valve completely
and not retain the spring compression, the
following procedure should be used:
- Remove the lever (27), forked lever (30),
cap (25) and spindle nut (23).
- Remove the nozzle ring set screw (4). Check
the setting of the nozzle ring (3) by turning it
to the right (counterclockwise), counting the
number of notches turned until it contacts
the disc holder (6) (see Figure 9). Record the
number of notches. This location is given
as minus (-) (down) or plus (+) (up) notches
from this level position.
- Remove the guide ring set screw (11).
The guide ring (10) should be turned to the
right (counterclockwise) or left (clockwise)
whichever is necessary to return it to its
level position. The guide ring is in level
position when the bottom face of the guide
ring is level with the bottom face of the disc
holder. The guide ring position is recorded
as minus (-) (down) or plus (+) (up) notches
from this level position.
- Measure and record spindle (12) to adjusting
bolt (21A) dimension A; and adjusting bolt
to bonnet (13), dimension B. See illustration
below.
- Release spring tension by loosening
the adjusting bolt nut (22) and then the
adjusting bolt (21A).
Bonnet (13)
Adjusting bolt nut (22)
Adjusting bolt (21A)
Spindle (12)
- Lift the spindle and internals carefully
straight up and out of the body (1A).
All the parts should be cleaned thoroughly,
paying special attention to guiding surfaces.
The seats should be lapped according to
section following 'Lapping or refurbishing
of valve seats'. If replacement parts are
required, refer to Section 2 - 'Ordering
spare parts'.
